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991.
The free settling behavior of the cylindrical particles made of four kinds of materials with horizontal motion in the stagnant water observed with an aid of the image sensor anemometer in the Reynolds number ranged from about 150 to 1000 was investigated in this paper. The four kinds of materials were finished into cylindrical specimens having the diameters “d” of 1.5 to 3.0 mm and the ratios of “d” to the length of specimen “1s” of d/1s = 1/2 to 1/3.5.
From the experimental results, the settling behavior of the particles was found to be simply expressed by the equation of a simple harmonic motion. By correcting the drag coefficient of the cylindrical particles with a correction factor which is obtained from the simple harmonic motion, the relationship between the drag coefficient and Reynolds number for the cylindrical particles was found to be parallel to that for the spherical particles. 相似文献
From the experimental results, the settling behavior of the particles was found to be simply expressed by the equation of a simple harmonic motion. By correcting the drag coefficient of the cylindrical particles with a correction factor which is obtained from the simple harmonic motion, the relationship between the drag coefficient and Reynolds number for the cylindrical particles was found to be parallel to that for the spherical particles. 相似文献
992.
Three models to estimate energy requirement as a function of growth curve pattern were applied to controlled experimental data of male vs female of broilers and turkeys. The share of maintenance out of total feed requirement was 55% for the average of the three models with major divergence due to age. Comparison of the ratio between actual and estimated feed consumption reveals that the relative energy requirement was always lower in females than in males in the range of 5 to 10% for the three models, with an average of 7.7%. It appears, therefore, that in estimating the energy requirement for use in practical feeding, specific models should be assigned for males and females in both broilers and turkeys. 相似文献
993.
Chaos and fractal responses from an artificial neural cell stimulated by a periodic square wave are discussed. The dynamics are described by an autonomous equation, and the one-dimensional return map is derived explicitly. The relation between the exciting pulse-width tau(1), and the excited rate gamma(e) which is the number ratio of input pulses and output pulses investigated. Mathematical evidence for gamma(e) to be Cantor function for tau(1) is given. It corresponds to fractal responses. A condition for observable chaos generation in responses from the cell is proved. This condition is described only by parameters. Some of the theoretical results are verified by laboratory experiments. 相似文献
994.
S Naito A Saito Y Furukawa T Hata Y Nakada S Muramatsu J Ide 《Canadian Metallurgical Quarterly》1994,47(7):812-820
Epoxidation reactions (MCPBA epoxidation and Sharpless epoxidation) were examined as a means of chemically modifying milbemycins as part of our program for discovering anthelmintics. 8,9-Epoxy-, 14,15-epoxy-, 8,9-14,15-diepoxy-, and 3,4-8,9-14,15-triepoxymilbemycin A4 were selectively obtained from milbemycin A4 and its derivatives, in which either the C-5 and C-7 hydroxyl groups or C-5 alone were protected as appropriate by a silyl ether (in the former case) or a carbonyl group. Further silylation or epoxidation on these epoxidized compounds indicated that the configuration of each epoxide moiety of the mono- and diepoxides is in accord with that of the corresponding epoxide moiety of the triepoxide. Furthermore, in order to confirm the absolute configurations of these epoxide functionalities, an X-ray analysis of a carbamate derivative from the triepoxymilbemycin was conducted. 相似文献
995.
H Saito 《Canadian Metallurgical Quarterly》1998,14(6):554-556
Both growth hormone (GH) and insulin-like growth factor 1 (IGF-1) are potent anabolic agents. Exogenous GH improves nitrogen metabolism in patients undergoing surgery; however, the anabolic effects of GH in cases of multiple injury, burn, and sepsis are equivocal. Moreover, few data are available concerning the effects of GH in organ failures. Exogenous IGF-1 attenuates catabolism in animal trauma models. A clinical trial, however, did not confirm the anabolic actions of IGF-1. Further knowledge of the interaction between the GH/IGF-1 axis in critical illness is essential for GH and IGF-1 therapy. Theoretically, the improved nitrogen metabolism achieved with exogenous anabolic agents may provide functional benefits. However, only a few studies have confirmed the beneficial effects of GH on body function in trauma and sepsis. GH treatment decreases the postoperative depression of hand grip strength. GH also stimulates wound healing. Both GH and IGF-1 exert their effects on immune system, suggesting that these anabolic agents are potentially beneficial for the prevention and treatment of sepsis. On the contrary, inhibition of polymorphonuclear neutrophil apoptosis and the potentiation of PMNs by GH may have harmful effects on the systemic responses. Further studies are required to determine the safety and clinical benefits of GH administration in critical illness. 相似文献
996.
H Akari Y Yamamoto H Hiwada Y Saito N Takayanagi AH Koyama A Adachi 《Canadian Metallurgical Quarterly》1998,44(3-4):211-214
Fasudil is a potent inhibitor for various protein kinases such as myosin light chain kinase and protein kinase C. It has been used as a drug for improvement of intracranial vasospasm and following ischaemic diseases. In this report, we demonstrate that fasudil suppressed the replication of human immunodeficiency virus type 1 (HIV-1) in mitogen-activated peripheral blood mononuclear cells. Our finding shows that fasudil may be useful as a new and distinct chemotherapeutic agent against HIV-1 infection. 相似文献
997.
Excellent performance of laminated Fe-Si-Al alloy film heads is demonstrated in applications to high-definition VCR and to digital recording. It is emphasized that these results are derived not only from the ring-shaped core geometry but also from the isotropic behavior in the magnetic properties of the sputtered Fe-Si-Al alloy films. The experimental results on the isotropic magnetic behavior are summarized. A mass-production process for the laminated alloy film heads is introduced, emphasizing the importance of stacked bar fabrication steps 相似文献
998.
999.
Shoichi Saito Tetsutaro Uehara Yutaka Izumi Yoshitoshi Kunieda 《Electrical Engineering in Japan》2006,154(2):40-51
The VPN (Virtual Private Network) technique is becoming increasingly popular as a way to protect the contents of messages and to achieve secure communications immune to such activities as eavesdropping. However, although VPN servers are increasingly used on a subnetwork in part of an officewide network, the PPTP system included in the Windows operating systems cannot establish nested VPN links. Moreover, encrypted communication by VPN hides the user of the VPN connection, and consequently the administrators of network systems cannot determine the users of the VPN connection via the firewall, or decide whether a user is legal or not. In order to solve this problem, we developed a multistep PPTP relay system on a firewall. This system solves all the problems of our previously developed PPTP relay system [1]. The new relay system improves security by end‐to‐end encryption of communication and eliminates the prior registration of passwords for the next step. Furthermore, the transport speed is increased and the restriction on the number of relay steps is also eliminated. These features of the multistep PPTP relay system expand its usability. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(2): 40–51, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20183 相似文献
1000.
A series of glucose oxidase (GOx) hybrids (GOx-phe-nothiazine-labeled poly(ethylene oxide) (PT-PEO)) capable of direct electrical communication with electrodes is synthesized by covalently modifying PT-PEO to lysine residues on the enzyme surface. The length of the PEO chain and the number of PT groups are systematically altered. After the PT-PEO modification, all the hybrids maintain more than 50% of enzyme activity relative to that of native GOx, although loss of the activity becomes greater with increasing PEO chain length. The catalytic current, i(cat), is observed at a potential more positive than 0.55 V after the addition of glucose, due to the intramolecular electron transfer (El) from reduced forms of flavin adenine dinucletide (FADH2/FADH) to PT+ that are electrogenerated at the electrode. The i(cat) value increases with the number of PT groups, indicating that most of the modified PT groups act as mediators. The magnitude of the i(cat) increase depends on the PEO chain length and reveals a maximum for PT-PEO with the molecular weight of 3,000. In contrast, the i(cat) is almost constant for GOx-2-(10-phenothiazyl)propionic acid (PT-PA) hybrids with more than two PT groups synthesized by covalently modifying PT-PA to surface lysines, indicating that only a few key PT groups function as mediators. The maximum rate constant (130 s(-1)) for the ET from FADH2/FADH to PT+ is obtained for the GOx hybrid modified with five PT-PEO groups with the molecular weight of 3,000. 相似文献